<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <!-- width:   px  百分比 -->
    <!-- 
    align="left right center"
    cellspacing="单元格与单元格之间的间隙"
    cellpadding="单元格与内容之间的间隙" 
    -->
    <table border="10" width="50%" height="300px" align="center"
    bordercolor="red" bgcolor="yellow" cellspacing="0" 
    cellpadding="100"
    >
        <tr>
            <td>1</td>
            <td>2</td>
        </tr>
        <tr>
            <td>3</td>
            <td>4</td>
        </tr>
    </table>
</body>
</html>